A moderate earthquake felt over a vast stretch of Southern California rattled the Greater Los Angeles area today and may have caused damage to a previously repaired section of the Santa Ana Freeway in Downey.
Updated 7:30 a.m.
The quake, which occurred at a depth of 11.2 miles, struck at 4:04 a.m., its epicenter 1 mile east-northeast of Pico Rivera and 11 miles east-southeast of downtown Los Angeles, according to the U.S. Geological Survey.
Some 50 minutes following the quake, the California Highway Patrol received reports of damage on the southbound Santa Ana (5) Freeway in Downey, just north of Lakewood Boulevard.
The damage consisted of broken concrete on two right-hand lanes in a section of the roadway that had been under repair. The CHP shut down the two lanes, resulting in a huge traffic backup, but the lanes were reopened about 6:30 a.m. after a temporary repair.
The same section of the roadway had been repaired before, and a more permanent repair was planned tonight, Caltrans reported.
Some uneven pavement also was reported on the northbound 5 Freeway at Norwalk Boulevard in Norwalk, but the lanes remained open and the pavement may have been that way before the temblor, the CHP reported.
The quake was felt as far away as San Diego County, according to reports received by the USGS.
In downtown Los Angeles, the temblor interrupted elevator service in the new Los Angeles Police Department headquarters across from City Hall. An elevator that goes to the third floor was still working, but employees on higher floors were being told they'd have to climb the stairs.
Several people reported hangings falling off their walls. There were no immediate reports of serious damage near the epicenter, but "we got several calls," said a watch deputy at the Pico Rivera Sheriff's Station. "People asked what was going on."
Deputies at the station also felt the jolt.
"It felt like something heavy dropped, twice, like back-to-back. Not like an earthquake. Like something heavy hit the ground," the watch deputy said.
Emergency dispatchers for Los Angeles County areas received no calls for service and no reports of damage, said dispatch Supervisor Robert Diaz of the Los Angeles County Fire Department.
Los Angeles Fire Department personnel were placed on "earthquake mode" status and many firefighters were sent out to check their districts for damage, said department spokesman Erik Scott.
"We had an influx of automatic 911 calls from building alarm systems," Scott said. "We have no reports of injuries related to the earthquake."
The quake's epicenter was in the Whittier Narrows area, site of a 5.9-magnitude quake that killed eight people in 1987, but Caltech seismologist Kate Hutton said that too much time has elapsed for this morning's shaker to have been an aftermath.
She also said it was not immediately clear along which fault line today's quake occurred.
Hutton said there is a 5 percent chance that this morning's temblor will be followed by magnitude 3 and 2 aftershocks – too small to cause major damage.